Re: 64-bits Plug-in instruments
There is no 64bit version of Sound Center although the 32bit version does work in 64bit SONAR. While it is still bundled with SONAR, the new SONAR includes Rapture Session which is 64bit and effectively replaces Sound Center.
I believe there is a 64bit version of Rapture LE. Which DAW did you purchase that included Rapture LE. There may be a 64bit version bundled with it.